ID NAME QUALITY USERS ACC % DIFFICULTY C I
31975 Ada and Scarecrow   14
50
50
32028 Ada and Parties   3
50
50
31979 Ada and Party   3 19
26
17
127 Johnny Goes Shopping   9 1507
20
24

#np-hard

NP-hard in computational complexity theory, is a class of problems that are, informally, "at least as hard as the hardest problems in NP"

https://en.wikipedia.org/wiki/NP-hardness https://en.wikipedia.org/wiki/Computational_complexity_theory https://en.wikipedia.org/wiki/P_versus_NP_problem https://en.wikipedia.org/wiki/NP_(complexity) https://en.wikipedia.org/wiki/Decision_problem